Covers for the protection of surfaces are commonly used to protect the ice surface in a hockey arena, for protection of artificial turf surfaces in indoor or outdoor stadiums, or to provide a modified surface other than, for example, concrete and the like, for both indoor and outdoor environments.
The prior art protective covering systems can include simple systems such as, for example, 4 by 8 foot sheets of plywood which are laid on the surface to be protected. A feature of this type of protective covering system is that it can be rapidly installed over a large surface, and thus allow for rapid conversion of, for example, the ice surface in a hockey arena, to allow for seating, for a concert or the like. The protective covering material can also be collected after use, stored, and reused in order to minimize costs. Further, the plywood sheets can be custom cut and saved to fit into areas of restrictive application, such as in the rounded corners of a hockey ice sheet.
However, use of simple plywood systems can lead to bending, shifting and buckling of the plywood, particularly if equipment, such as fork lifts or the like, are driven on the plywood surface. This can lead to the formation of small gaps between the plywood sheets which can cause tripping hazards, or which can trap the wheels of dollies or other equipment traveling over the protective covering surface. Use of tongue and groove plywood might overcome some of these problems, but this material would not be suitable for all applications since this system could not be rapidly or easily installed, and the tongue and groove feature could be easily damaged during routine installation or removal.
A further problem with this type of system is that it provides little if any significant insulation. This can be an important considerations if the protective surface is installed over an ice surface, or frozen wet ground where it would be desirable to provide a warmer floor temperature for those using the arena or site and provide for reduced cooling costs for maintaining the ice surface temperature under the protective covering.
Small-area systems are also known, having panels which are typically less than 5 square feet in surface area. Because of their small size, installation of these systems can take considerable time. Accordingly, it is generally preferred to use “large-area” panels each of which has a surface area of at least 10 sq. ft.
In U.S. Pat. No. 3,870,587 (Merrell), an ice rink cover is described having an insulated core, a wooden frame, and a simple “hand holds” to facilitate lifting and movement of the panes. Staten et al., in U.S. Pat. No. 5,820,798 and related U.S. Pat. No. 5,983,584, describe an ice rink cover which is produced by combining two identical plastic panels to form a combined protective covering panel which has an internal support structure consisting of aligned pillars from the upper and lower panel surfaces.
Accordingly, while the prior art systems have adequate protective covering properties, it would be advantageous to provide a large-area protective panel which would provide improved protective covering properties, while facilitating installation and removal of the protective covering.